[20260514] - Core - Privilege escalation through com_users webservice endpoints

Project: Joomla!
SubProject: CMS
Impact: High
Severity: Moderate
Probability: Low
Versions: 4.0.0-5.4.5,6.0.0-6.1.0
Exploit type: Privilege Escalation
Reported Date: 2026-04-15
Fixed Date: 2026-05-26
CVE Number: CVE-2026-48904

Description

An improper access check allows privelege escalation through the com_users group editing webservice endpoint.

Affected Installs

Joomla! CMS versions 4.0.0-5.4.5,6.0.0-6.1.0

Solution

Upgrade to version 5.4.6,6.1.1

Contact

The JSST at the Joomla! Security Centre.

Reported By: Christos Papakonstantinou, Cantina